1. Field of the Invention
The present invention relates in general to an air breather device of an automotive transmission, and more particularly to an air breather device of an automotive manual transmission adaptable for use in a front-wheel-drive automotive vehicle having a transverse mounted engine.
2. Description of the Prior Art
In order to keep the inside pressure of the transmission at atmospheric level, a so-called air breather device is mounted to the transmission, which permits introduction of ambient air into the transmission open air or air discharge from the transmission into the air in accordance with the pressure difference created between the inside of the transmission and the ambient air.
In conventional air breather devices, an arrangement is usually employed in which a cover covering an open end of the transmission housing is formed with a recess facing toward the inside of the housing. A breather port is formed in the cover to communicate the recess with ambient air, and a separate plate partially covers the recess thereby permitting the inside of the recess (breather chamber) to communicate with the inside of the transmission housing through the remaining open section of the recess. Thus, under operation, the air breathing is carried out through the breather port, the breather chamber and the remaining open section.
In this type air breather device, however, mounting of the separate plate to the recess requires troublesome positioning work and in addition to this, the lubricant oil in the housing tends to form its film on the recess because of its inherent construction, causing malfunction of the device, so that it often happens that the lubricant oil in the transmission housing is blown off through the device.